Replaceable pad assembly

ABSTRACT

A replaceable resilient pad assembly for abrasive finishing articles. A body of resilient material has a drive disc secured to one side of the body. The other side of the body contains a surface to which an abrasive finishing article can be secured. The drive disc contains drive bosses which enable the assembly to rotate with a drive member. An inwardly-directed lip formed on the periphery of the drive disc enables the disc to be positioned on the drive member without the use of tools or an adhesive. Typically, the drive disc is a flexible plastic member having integrally formed drive bosses and lip.

[ 1 Feb. 18, 1975 I 1 REPLACEABLE PAD ASSEMBLY [75] Inventor: Harold R.Mauck, Woodland Hills,

Calif.

[73] Assignee: Standard Abrasives Incorporated,

Northridge, Calif.

[22] Filed: Aug. 22, 1973 [21] Appl. No.: 390,642

[52] US. Cl 51/358, 51/378, 51/389 [51) Int. Cl. B2411 17/00 [58] Fieldof Search 51/358, 376-379, 51/389, 390

[56] References Cited UNITED STATES PATENTS 3,014,319 12/1961 Olton51/358 3,082,582 3/1963 Jeske 51/358 3,241,268 3/1966 Olson 51/3583,510,992 5/1970 Hutchins 51/358 FOREIGN PATENTS OR APPLICATIONS 710,9456/1931 France 51/379 Primary E.\'uminer-Othell M. Simpson Attorney,Agent, or FirmNilsson, Robbins, Bissell, Dalgarn & Berliner [5 7]ABSTRACT A replaceable resilient pad assembly for abrasive fin ishingarticles. A body of resilient material has a drive disc secured to oneside of the body. The other side of the body contains a surface to whichan abrasive finishing article can be secured. The drive disc containsdrive bosses which enable the assembly to rotate with a drive member. Aninwardly-directed lip formed on the periphery of the drive disc enablesthe disc to be positioned on the drive member without the use of toolsor an adhesive. Typically, the drive disc is a flexible plastic memberhaving integrally formed drive bosses and lip,

3 Claims, 3 Drawing Figures 1 REPLACEABLE PAD ASSEMBLY BACKGROUND OF THEINVENTION 1. Field of art The field of art to which the inventionpertains includes the field of abrasive finishing articles, particularlywith respect to a replaceable, resilient pad assem bly for supportingsuch articles.

2. Description of the prior art Resilient pad assemblies which are usedto support abrasive finishing articles are typically made so that thefinishing article can be quickly connected to a drive member and thendisconnected when it is desired to use a fresh or different finishingarticle. Typically, the used finishing disc can either be replaced onits support surface at a later time or preferably, the disc and itssupport surface discarded.

Conventional pad assemblies are formed of a single unit containing adrive stud and suitable support plates. The support plates are typicallyformed of phenolic fiber or metal discs, or both, which are rivetedtogether and contain a sponge element permanently bonded to the frontface of the disc. If the sponge element wears out or is torn, the entireunit must be replaced. Normally, the cost of a main drive member is muchgreater than the finishing article and the support member. Thus, it hasbeen found desirable to merely discard the finishing article and supportmember and provide fresh assemblies which can be secured to a main drivememher.

The present invention provides a replaceable resilient pad assemblywhich can be easily mounted on a drive member. An abrasive article canbe secured to one side of a resilient member of the pad assembly withthe other side of the resilient member having a drive disc securedthereto. The pad assembly is easily positioned on the drive memberwithout the use of tools or adhesives.

SUMMARY OF THE INVENTION A resilient pad assembly includes a body ofresilient material with one face adapted to have an abrasive finishingarticle secured thereto, and a drive disc secured to the other face. Thedrive disc is integrally formed with both a plurality of bosses and aninwardly turned lip on its periphery. The bosses fit into aperturesformed in the drive member and the lip is secured around the peripheryof the drive member'and secures the drive disc to the drive member. Thebosses enable the drive disc to turn with the drive member.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective viewof a resilient pad assembly as well as a drive member utilized to drivethe pad assembly;

FIG. 2 is a fragmentary view, partly in section, of the resilient padassembly of FIG. I mounted on the drive member; and

FIG. 3 is a fragmentary view in section, illustrating the technique ofremoving the replaceable pad assembly from the drive member.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. I, thereis shown a resilient pad assembly 12 constructed in accordance with theprinciples of the invention together with a drive member 14 upon whichthe pad assembly may be mounted. The resilient pad assembly 12 isillustrated in FIG. 1 in an exploded perspective view prior to assemblyin a sandwich configuration.

The pad assembly 12 comprises a resilient pad 22 shaped as a disc-likemember having a central opening 24 formed therein. The resilient pad 22is a relatively thick, flat circular pad made of foam rubber,polyurethane, or an equivalent foam material which has an internal cellstructure. A drive disc 26 and a face member 28 are secured on oppositefaces of the pad 22. The face member 28 is normally made of duck clothor similar type material and has a diameter approximately equal to thatof the pad 22. The face member 28 contains an opening 30 (not shown inFIG. 1) which is aligned with the opening 24 of the pad 22.

The drive disc 26 diameter is slightly less than the diameter of the pad22. The disc 26 contains an annular inwardly-directed retaining lip 32formed on its periphery. The lip 32 is formed on the surface of the disc26 opposite that secured to the pad 22. The annular lip 32 is chamferedon both sides to facilitate insertion and removal of a drive member aswill be explained hereinafter. A drive disc central opening 34 is equalin size and aligned with the openings in the pad 22 and face member 28.A plurality of equally spaced bosses 36 are formed on the surface of thedrive disc opposite to that of the surface adjacent the pad 22.Typically, the drive disc 26 is made of a low density polyethylene,although polypropylene, polyvinylchloride or similar type mate rialscould be used as well. Normally, the drive disc 26 is molded so that theinwardly-directed lip 32 and the bosses 36 are integrally formed withthe drive disc. The bosses 36 are illustrated as being cylindrical inshape, with the axes thereof perpendicular to the plane of the drivedisc, although other shapes could be utilized.

The drive disc 26 and face member 28 are, previously pointed out,positioned on opposite sides of the pad 22. Typically, an adhesive, suchas an acetone base-type material, could be used to secure the drive disc26 and face member 28 to the pad 22, although other adhesives could workas well. The exterior surface of the face member has an abrasivefinishing article 38 secured thereto, also by an adhesive, with theouter surface of the finishing article 38 having finishing material 42(shown in FIG. 2) thereon. Normally, the replaceable pad assembly 12formed of the pad 22, the drive disc 26, and the face member 28, is soldas a single integral package for replacement on the drive member 14. Ofcourse, the finishing article 38 could be included in such a package.

The drive member 14 is formed of a main plate 52 whose diameter isslightly less than that of the drive disc 26. Referring to FIG. 2, thediameter of the main plate 52 is such that the inwardly turned lip 32can be slipped over the outer edge 53 of the main plate. The lip thensecurely holds the main plate to the drive disc. The main plate 52further contains a plurality of spaced boss openings 54 which arealigned with the bosses 36 in the drive disc 26. When the drive disc ispositioned over the main plate 52, the bosses 36 are aligned with theboss openings 54 and are inserted therein. While the embodimentillustrated in FIG. 1 depicts four bosses which are insertable in theboss openings in the main plate, it should be understood that only aminimum of two bosses are necessary for stability, but there is no upperlimit on the number of bosses which could be utilized to interconnectthe drive disc 26 and the main plate 52. The limit on number of bosseswill depend upon the drive torque needed to rotate the pad assembly.Typically, the size of the bosses has been found to be not critical.

The main plate 52 further contains a central opening 56 which is alignedwith the central openings in the pad assembly 12, but is of a smallerdiameter. A pair of backing plates 62 and 64 having central openings 66and 68, respectively, are positioned so that the plate 62 is sandwichedbetween the plates 52 and 64. The plates are secured together by meansof a bolt 72 whose threaded shaft 74 extends through the centralopenings in the plates 52, 62 and 64. The plates are secured in thesandwich fashion by means of a locking nut 76 which is secured to athreaded shaft 74 of the bolt 72. The bolt 72 further contains anenlarged head portion 78 whose diameter is such that it can fit into theopenings in the drive disc 26 and pad 22 when the drive disc is securedto the main plate 52 thus assuring correct alignment of the pad assembly12 and drive member 14 during assembly. However, the opening 24 in thepad 22, and the opening 34 in the drive disc 26 are not necessary to theoperation of the assembly. In place of the bolt 72, it should beunderstood that other securing arrangements such as rivet could be usedto secure the plate 52, 62 and 64 together, the bolt arrangementillustrated in FIGS. 1 and 2 being merely illustrative of one type ofsecuring arrangement. In addition, the main plate 52 and the backingplates 62 and 64 could be formed of either rigid plastic or metal as isneeded for the type of use.

The threaded shaft 74 of the bolt forms a spindle for rotating the drivemember 14. Rotation of the drive member will impart movement of the padassembly 12. The bosses 36 cause the drive disc 26 to rotate with themain plate 52. Should it be necessary to replace the pad assembly 12, aswhen the finishing material 42 on the finishing disc 38 wears out, or adifferent type of finishing material be desired, it is merely necessaryto remove the pad assembly 12 by bending the lip 32 slightly back asshown in FIG. 3, thus enabling the pad assembly to be removed and a newpad assembly to be inserted thereon without the use of tools oradhesives.

I claim:

1. A replaceable pad assembly comprising:

a body of resilient material having a first side face and a second sideface;

means for securing an abrasive finishing article to one of said sidefaces; and

a generally planar drive disc having one surface secured to the other ofsaid side faces and a second surface having drive bosses integrallyformed thereon for enabling said assembly to rotate with a drive memberhaving openings into which said drive bosses are inserted;

means formed on said drive disc for securing said drive disc to saiddrive member consisting of an annular inwardly-directed retaining lipformed on the periphery of said drive disc chamfered for facilitatinginsertion and removal of said drive member, said drive disc peripherybeing sufficiently flexible to enable said drive disc to be rapidlyseparated from said drive member.

2. A replaceable pad assembly in accordance with claim 1 wherein saiddrive disc contains a central opening for insertion of a drive shaftsecured to a drive member.

3. A replaceable pad assembly in accordance with claim 1 wherein saiddrive disc is formed of a molded plastic member with said drive bossesand said inwardly turned lip being integrally formed therewith.

1. A replaceable pad assembly comprising: a body of resilient materialhaving a first side face and a second side face; means for securing anabrasive finishing article to one of said side faces; and a generallyplanar drive disc having one surface secured to the other of said sidefaces and a second surface having drive bosses integrally formed thereonfor enabling said assembly to rotate with a drive member having openingsinto which said drive bosses are inserted; means formed on said drivedisc for securing said drive disc to said drive member consisting of anannular inwardly-directed retaining lip formed on the periphery of saiddrive disc chamfered for facilitating insertion and removal of saiddrive member, said drive disc periphery being sufficiently flexible toenable said drive disc to be rapidly separated from said drive member.2. A replaceable pad assembly in accordance with Claim 1 wherein saiddrive disc contains a central opening for insertion of a drive shaftsecured to a drive member.
 3. A replaceable pad assembly in accordancewith Claim 1 wherein said drive disc is formed of a molded plasticmember with said drive bosses and said inwardly turned lip beingintegrally formed therewith.